What was found
JFK - DURING CLIMB THROUGH FL300 WITH AUTOPILOT OFF, EXPERIENCED A SHARP NOSE UP JERKING MOTION. LEFT ELEVATOR POSITION INDICATOR INDICATING UP AND DOWN DEFLECTIONS. POSITIONED HYDRAULIC SYSTEM IN FLIGHT CONDITION. HYDRAULIC POWER SWITCH TO CLOSED, THE UNUSUAL MOTION STOPPED. REMOVED AND REPLACED RIGHT INBOARD ELEVATOR POWER CONTROL PACK PER MM 27-31-07, OPS CHECK GOOD. (M)